Surgical methods to reverse left ventricular remodeling in congestive heart failure

Anesthetic Considerations for a Novel Method of Surgical Ventricular Remodeling Using the BioVentrix Revivent TC System

Surgical ventricular remodeling (SVR) is an invasive method of treating patients with heart failure who also have ischemic cardiomyopathy and reduced ejection fraction (EF). Introduced in the mid-1980s, this technique was met with varying success and relatively high morbidity and mortality despite its theoretical benefits. The development of the BioVentrix Revivent TC System (BioVentrix, Inc., San Ramon, CA) as a less-invasive method of surgical ventricular remodeling has created a novel, multidisciplinary approach to heart failure management, which necessitates multiple subspecialties. Currently in the trial phase in the United States and widely used in Europe, the positive results to date appear promising for the rapid adoption of this procedure. For the cardiac anesthesiologist, a thorough understanding of the patient population, procedural goals, and intraoperative management is essential. This overview discusses the advancement in surgical ventricular remodeling, the pertinent surgical steps of the BioVentrix Revivent TC System placement, and specific anesthetic considerations for this novel procedure.

Transseptal and transmitral Parachute® implantation in conjunction with "MitraClipping"

AIMS

Parachute® implantation (PI) is an attractive treatment option for patients with left ventricular apical aneurysms (LVAA). So far, only the retrograde approach has been approved for PI. Unfortunately, severe functional mitral regurgitation (MR) restricts PI. Thus, we were intrigued to combine PI and MitraClip therapy (MCT) as a new transvenous hybrid concept.

METHODS AND RESULTS

PI was performed via a transseptally placed MitraClip guide in six consecutive patients (age 73.8±5.2; 66% male). Immediately after PI, MR was treated by MCT. Invasive right and left heart haemodynamics were taken before and after PI and MCT, respectively. Procedural success was 100%. PI induced a numerical increase in cardiac output (CO: +36.4; p=0.15) and stroke volume (SV: +30.1%; p=0.09), despite some evidence of MR aggravation. Subsequent MCT successfully reduced MR at least to mild in five patients and to moderate in one patient. SV and CO demonstrated a further increase (SV: +44.3%, p=0.03; CO: +44.5%; p=0.03).

CONCLUSIONS

The study documents for the first time the feasibility of transseptal and transmitral PI. Nevertheless, pre-procedural MR seems to counteract the beneficial effects of PI. Hence, the combined transseptal approach of PI and MCT seems to be the appropriate strategy in patients with significant MR and LVAA.

Percutaneous left ventricular partitioning in patients with chronic heart failure and a prior anterior myocardial infarction: Results of the PercutAneous Ventricular RestorAtion in Chronic Heart failUre PaTiEnts Trial

OBJECTIVES

The aim of this study was to assess the feasibility, safety, and preliminary efficacy of a novel percutaneous left ventricular partitioning device (VPD) in patients with chronic heart failure (HF) and a prior anterior myocardial infarction.

BACKGROUND

Anterior myocardial infarction is frequently followed by left ventricular remodeling, HF, and increased long-term morbidity and mortality.

METHODS

Thirty-nine patients were enrolled in a multinational, nonrandomized, longitudinal investigation. The primary end point was an assessment of safety, defined as the successful delivery and deployment of the VPD and absence of device-related major adverse cardiac events over 6 months. Secondary (exploratory) efficacy end points included changes in hemodynamics and functional status and were assessed serially throughout the study.

RESULTS

Ventricular partitioning device placement was not attempted in 5 (13%) of 39 subjects. The device was safely and successfully implanted in 31 (91%) of the remaining 34 patients or 79% of all enrolled patients. The 6-month rate of device-related major adverse cardiac event occurred in 5 (13%) of 39 enrolled subjects and 5 (15%) of 34 treated subjects, with 1 additional event occurring between 6 and 12 months. For patients discharged with the device to 12 months (n = 28), New York Heart Association class (2.5 ± 0.6 to 1.3 ± 0.6, P < .001) and quality-of-life scores (38.6 ± 6.1 to 28.4 ± 4.4, P < .002) improved significantly; however, the 6-minute hall walk distance (358.5 ± 20.4 m to 374.7 ± 25.6 m, P nonsignificant) only trended toward improvement.

CONCLUSIONS

The left VPD appears to be relatively safe and potentially effective in the treatment for patients with HF and a prior anterior myocardial infarction. However, these limited results suggest the need for further evaluation in a larger randomized controlled trial.

Coronary bypass surgery with or without surgical ventricular reconstruction

BACKGROUND

Surgical ventricular reconstruction is a specific procedure designed to reduce left ventricular volume in patients with heart failure caused by coronary artery disease. We conducted a trial to address the question of whether surgical ventricular reconstruction added to coronary-artery bypass grafting (CABG) would decrease the rate of death or hospitalization for cardiac causes, as compared with CABG alone.

METHODS

Between September 2002 and January 2006, a total of 1000 patients with an ejection fraction of 35% or less, coronary artery disease that was amenable to CABG, and dominant anterior left ventricular dysfunction that was amenable to surgical ventricular reconstruction were randomly assigned to undergo either CABG alone (499 patients) or CABG with surgical ventricular reconstruction (501 patients). The primary outcome was a composite of death from any cause and hospitalization for cardiac causes. The median follow-up was 48 months.

RESULTS

Surgical ventricular reconstruction reduced the end-systolic volume index by 19%, as compared with a reduction of 6% with CABG alone. Cardiac symptoms and exercise tolerance improved from baseline to a similar degree in the two study groups. However, no significant difference was observed in the primary outcome, which occurred in 292 patients (59%) who were assigned to undergo CABG alone and in 289 patients (58%) who were assigned to undergo CABG with surgical ventricular reconstruction (hazard ratio for the combined approach, 0.99; 95% confidence interval, 0.84 to 1.17; P=0.90).

CONCLUSIONS

Adding surgical ventricular reconstruction to CABG reduced the left ventricular volume, as compared with CABG alone. However, this anatomical change was not associated with a greater improvement in symptoms or exercise tolerance or with a reduction in the rate of death or hospitalization for cardiac causes. (ClinicalTrials.gov number, NCT00023595.)

Left Ventricular Spherical Remodeling and Apical Myocardial Relaxation: Cardiovascular MR Imaging Measurement of Myocardial Segments

PURPOSE

To prospectively evaluate left ventricular (LV) shape and regional relaxation to determine if rapid, early relaxation of the LV is lost with spherical remodeling of the LV.

MATERIALS AND METHODS

This HIPAA-compliant study was approved by the institutional review board. All participants gave written informed consent. Cardiovascular magnetic resonance (MR) imaging and transthoracic echocardiography (TTE) were performed in 18 individuals. Each participant was classified into one of three groups according to LV shape and TTE-derived mitral filling parameters. Pairwise comparisons of cardiovascular MR imaging measurements of LV relaxation were made between healthy individuals and those with spherically shaped LVs.

RESULTS

The LV regional relaxation rates were determined in a total of 108 basal, middle, and apical myocardial segments in 18 participants (13 women, five men; age range, 35-76 years). Participants with a spherically shaped LV (sphericity index, <1.5) and a mitral inflow velocity E wave/A wave ratio of less than 1.0 exhibited apical thinning velocities that were lower than those of healthy individuals (sphericity index, > or =1.5) (P < .01). The ratio of LV relaxation velocities in the apical versus middle LV segments correlated significantly with sphericity index (R(2) = 0.53; P = .0005).

CONCLUSION

LV apical relaxation velocities in participants with LV spherical remodeling (sphericity index, <1.5) were reduced compared with those of healthy individuals (sphericity index, > or =1.5).

Feasibility of arresting the process of remodeling

Heart failure (HF) is a massive public health issue. Ventricular remodeling is pivotal to the pathophysiology/progression of HF and an attractive target for intervention. It currently is believed that interdicting the natural history of ventricular remodeling will be crucial to controlling the HF epidemic. This article reviews the current data on the feasibility of arresting this process. This review is not meant to be exhaustive but provides a brief overview of the approaches being contemplated in this field.